1. Field of the Invention
This invention relates to transporters for vertically raising bulk material and more particularly to apparatus mounted on the transporter for dislodging bulk material and drawing it toward the transporter.
2. Prior Art
As bulk cargo ships have grown larger, continuous type unloaders, such as bucket ladders, have been increasingly employed to raise the bulk material from the ships' holds. An example of such an unloader is disclosed in U.S. Pat. No. 3,847,270. Belt conveyors have also been employed to remove bulk material from smaller vessels such as barges.
Various devices have been proposed for drawing material toward the vertical transporter. U.S. Pat. Nos. 3,595,405 and 3,823,915 disclose the use of a bucket wheel to load bulk material from a vessel onto a belt conveyor and a bucket ladder respectively. The first of these patents also discloses the use of a backhoe device to draw material toward the bucket wheel. U.S. Pat. No. 2,773,608 suggests a somewhat similar type of device for drawing material toward a conveyor in the form of fingers mounted eccentrically on rotating discs placed in front of the conveyor. It has also been proposed in U.S. Pat. No. 3,770,145 to use movable plows to direct material toward a barge unloader.
One of the drawbacks of the prior art devices is that they lack maneuverability and therefore have a limited capability of dislodging material and gathering it inward from all around the transporter. This is a significant shortcoming in unloading bulk material through a hatch where material under the deck and in the corners must be drawn to the transporter for efficient unloading. The prior art devices are also generally bulky which is a limiting factor in adapting them for unloading ships through a hatch. A primary object of the present invention is to provide a bulk material dislodging and gathering device which is highly maneuverable such that it can dislodge and gather bulk material from all around the transporter especially under the deck of a ship and in the corners of a hold, yet is compact enough that it can be inserted and withdrawn through restricted hatch openings.